Description of the Prior Art
The present invention relates to improvements to compound handbows, and is particularly directed to a grip, arrow and arrow rest arrangement which substantially reduces the overall size of the bow, eliminated inherent and subsequent torques which reduces accuracy and teaches a new method of shooting which improves the viewing of the target.
Compound bows employ a relatively complex cable and pulley arrangement in which the geometry of the system is quite critical. Due to the use of a system of multiple pulleys mounted on the bow, around and through which the bowstring is strung, maximum draw pressure is exerted only during the first half or two-thirds of its displacement. As the bowstring is drawn back toward its maximum deflection, a sudden drop in draw pressure is experienced and the archer may easily draw the bowstring back through its remaining draw distance. Thus, accuracy is greatly enhanced because the draw pressure exerted on the bowstring, when fully drawn back, is relatively small. By using the pulleys, not only is the draw pressure at full draw distance greatly reduced, by the length of the bow is also minimized since a relatively long bowstring may be used and wound around the pulleys in such a manner as to shorten the total length of the bow. However, a typical compound bow is still relatively long, and hence, relatively awkward to carry, especially through heavy underbrush conditions typically encountered during archery hunting.
Of particular concern in the design of compound bows is the relatively lengthy central body portion located between the inner ends of the tensionable limbs. This central body incorporates three essential elements, the sight window, arrow passage and the handle grip, in the longitudinal bow plane, thus accumulatively lengthening the overall dimension of the bow. More specifically, an offset upper portion is required to allow the arrow to lie in the longitudinal bow plane defined by the tensionable limbs, central body portion and bowstring and also to provide a sight window for the archer since, in the vertically upright position in which the bow is held, the body portion will normally block the archer's view. Additionally, at a position below the offset portion as described previously, the handle extends vertically at a position which is in line and parallel to the longitudinal axis of the bow. The placement of the handle in the central body portion of the bow disposed, as it is, below the offset portion and in a vertical orientation results in a substantial height of the central portion.
When designing a compound bow, it would be desirable to have the arrow, as it is drawn and shot, positioned in the bow plane as to bisect the bow's overall length, as defined by the distance between the bow string's anchoring points upon the outermost end of the tensionable limbs. Having the arrow in this bisecting position as the bow is fully drawn, the angles produced between the arrow and the string are equal on either side. Thus when released, forces produced by each tensionable limb are equally transferred to the arrow. It would also be desirable to have the cup portion of the hand grip, as defined by the radius formed in the grip to accept the cupped portion of the holding hand being at the base of the thumb and index finger, to be located in the bow plane and in the bisecting plane of the bow's overall length, as defined previously. When drawing the bow string, this position balances the tensionable limb force on the bow holding hand. Thus the bow can be drawn without any rotational tendencies about the bow holding hand.
An inline arrangement of the hand grip and arrow position cannot accomplish the desired location of both. This is due to the fact that the arrow would have to pass through the archer's bow holding hand. Thus a compromise with either or both positions is required, resulting in a design which has forces inherently imbalanced. This imbalance of force puts a torque on the archer's holding hand and/or creates a misaligned thrust on the arrow.
A second torque induced while shooting a typical compound bow is not inherent to the offset relation of the arrow axis to the grip, but, due to an archer's grasp on the handle. If an archer happens to grasp the bow, as to twist the handle, while in the fully drawn position at the time of release of the arrow, a misalignment occurs which angles the bowstring away from its normal plane of travel. When the archer releases the bowstring, thus launching the arrow, the misaligned string realigns during the stroke of the string resulting in a deflecting action to the arrow's flight. These problems will combine to greatly decrease the accuracy of the archer using a standard bow.
Given the fact that different archers have different physiques, some adaptation of the archer to the particular bow is normally required. The optimum full-draw position of the bow involves the gripping of the bow with one hand and the drawing back of the string with the other until the string touches the archer's cheekbone below his sighting eye. The arm holding the bow is thus extended to establish the draw length at the correct distance forwardly from the fixed reference point constituted by the archer's cheekbone. Where the grip is in a permanently fixed relationship to the bow limbs, as described above, archer's with different draw lengths are required to fit the bow with specific pulleys having either larger of smaller circumferences to accommodate the individual archer's draw.
The present invention is especially directed to an asymmetrical pistol grip assembly adapted for compound bow usage which includes an arrow positioning arrangement which accomodates positive positioning of the arrow at the center line of the bow plane and which removes the grip and sight window from the central portion of the body thereby greatly reducing the bow height and placing the grip at a position which eliminates misdirecting torques applied upon the arrow.